The Application of Shallow Structural Mapping to Understand the Deep Structure in the October Field Area, Northern Suez Rift, Egypt

By

 Mohamed Maged¹

(1) Gupco, Cairo, Egypt

 Many Gulf of Suez oil fields produce from pre-rift, Paleozoic through Cretaceous aged reservoirs located in the footwalls of tilted fault blocks bounded by NNW-SSE striking (rift-parallel) normal faults. However, in some cases, faults oriented in directions oblique to the axis of the rift serve as bounding faults for oil accumulations. Correct understanding of these structural elements is key to success in finding new fields. However, seismic imaging across much of the Gulf of Suez is difficult because of mid Miocene, syn-rift evaporate-rich intervals, which generate multiples that mask the primary energy.

Many methods have been developed to enhance seismic data quality, and to improve the confidence of using seismic data for structural interpretation. We demonstrate the use of some simple mapping techniques in the shallow syn-rift section, above the effects of multiples where the seismic images is more reliable, to better understand structure at deeper pre-rift reservoir levels. The techniques used include the generation of late syn-rift structure and isopach maps, 3D displays, and integration with onshore geology and edge detection maps.

The application of these techniques allows us to identify linkages between late rift and early rift structures and how these linkages vary with respect to salt thickness. It allows us to identify subtle structures, and can be used as a tool for quick regional interpretation and to constrain the structural geometry of oil fields.